Comparative effects of polystyrene nanoplastics with different surface charge on seedling establishment of Chinese cabbage (Brassica rapa L.). (April 2022)

• Record Type: Journal Article
• Authors: Zhang, Hui; Liang, Jie; Luo, Yuan; Tang, Ning; Li, Xin; Zhu, Ziqian; Guo, Jiayin
• Is Part Of: Chemosphere. Volume 292(2022)
• Publication Date: 2022-04
• Subjects: Polystyrene nanoplastics (PSNPs) -- Surface charge -- Seedling establishment -- Skotomorphogenesis -- Photomorphogenesis; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.133403
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Micro- and nano-plastics are common emerging pollutants of great interest. However, the impacts of them on terrestrial plants were still poorly understood. In this study, comparative effects of exposure of polystyrene nanoplastics (PS) and amino-modified polystyrene nanoplastics (PS-NH2 ) on Chinese cabbage ( Brassica rapa L.) plants at different growth stages were investigated. Hydroponically cultured seedlings were exposed to PS and PS-NH2 at 0, 1, 10, and 100 mg/L at skotomorphogenesis stage for 48 h, photomorphogenesis stage for 18 h, and the whole stage, respectively. Results showed that both PS and PS-NH2 had no discernible effect on radicle elongation at the skotomorphogenesis stage whereas significantly ( P < 0.05) reduced photosynthetic pigment contents in varying degrees (18.06%–28.52%, 22.46%–36.86%) at the photomorphogenesis stage and the whole stage. Moreover, there was no significant difference between PS treatments and control except the 26.52% decline of chlorophyll a content at 1 mg/L at photomorphogenesis, while PS-NH2 significantly ( P < 0.05) decreased photosynthetic pigment contents except the chlorophyll b content at 10 mg/L at photomorphogenesis. The content of chlorophyll a decreased by 26.68% for the PS–NH2 –treated group and 22.46% for the PS-treated group at 1 mg/L during the whole stage. Results manifested that less negatively charged PS-NH2 seemed to show more severe phytotoxicity both at the photomorphogenesis stage and the whole stage. Notably, the surface charge of nano-plastics and the integrity of seedling establishment could be the main factors impacting the above difference. These findings are expected to improve our understanding of the effects of PSNPs on crop plants. Graphical abstract: Image 1 Highlights: Radicle growth was not affected significantly by exogenous applied PSNPs. Photosynthetic pigment contents decreased in varying degrees in response to PSNPs. The amide functional group of PS-NH2 was involved in its phytotoxicity. Whether or not exposure of PSNPs at skotomorphogenesis was also a key factor.